There is an exemplary technique of reducing the size of a base station for radio communications by providing a door that opens and closes a plurality of faces of a housing body, and a door pocket that receives the door, when opened, in such a manner as to draw the door into the housing body (see Japanese Laid-open Patent Publication No. 2008-244185, for example).
There is another exemplary technique of reducing the size of an electronic apparatus by fastening a first housing and a second housing, which together form a housing, to each other by fitting a tab of the first housing into a holding recess of the second housing (see Japanese Laid-open Patent Publication No. 2006-216724, for example).